Multi-stand rolling mills require critical alignment of the reducing rolls and the guiding devices which feed the work product to the reducing rolls. If for some reason, misalignment between the guide and reducing rolls occurs during a rolling process, the result is often a damaged or “off-gauge” product which may not be marketable. It is therefore essential to have the guiding device in exact alignment with the reducing rolls during a reduction process. Because of the location of the main reducing rolls and the low light levels existing at this location, the adjustment of the guide rolls to their proper setting can present a challenge to a mill technician.
Rolling mills traditionally present an environment which tends to be hostile for most alignment instruments. Usually alignment of the guides and reduction rolls must be accomplished in the shortest possible time under conditions which are less than ideal. The mill usually operates at an elevated temperature with coolant water being copiously applied to the surface of the guide rolls and the reduction rolls.
In most instances the “throat” of the guide is obscured by auxiliary apparatus and the levels of light existing at the guide throat and the main roller “nip” leaves a lot to be desired.
It is therefore seen that even if one was able to adjust the alignment of the guide and its rollers to the correct position to feed the reduction rolls of the mill, the adjustment procedure places an almost impossible task on the mill technician due to the fact that the critical zones of the mill i.e. the main roller gap and the guide throat are almost inaccessible to the human eye.